# GO-2021-0091 - Due to improper input validation when uploading a file, a malicious user may force the server to return…

Source: https://junglewise.ai/threats/go-2021-0091-due-to-improper-input-validation-when-uploading-a-file-a-ba9e7515  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-04-14  
License: CC BY 4.0 with a link back

Severity: info · Published 2021-04-14

Due to improper input validation when uploading a file, a malicious user may
force the server to return arbitrary HTTP headers when the uploaded
file is downloaded.

Technologies: [github.com/gofiber/fiber (Go)](https://junglewise.ai/threats/technologies/github-com-gofiber-fiber). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Informational severity, published 14 April 2021.

**Which products and versions are affected?** github.com/gofiber/fiber (Go) SEMVER:introduced=0,fixed=1.12.6-0.20200710202935-a8ad5454363f.

**Is there a fix for This vulnerability?** Yes. github.com/gofiber/fiber (Go): upgrade to 1.12.6-0.20200710202935-a8ad5454363f or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected?** Check whether you run github.com/gofiber/fiber (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/gofiber/fiber (Go): upgrade to 1.12.6-0.20200710202935-a8ad5454363f or later

  ```sh
  go get github.com/gofiber/fiber@v1.12.6-0.20200710202935-a8ad5454363f
  ```


## Affected products

- github.com/gofiber/fiber (Go) SEMVER:introduced=0,fixed=1.12.6-0.20200710202935-a8ad5454363f

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